Error: Could not load file or assembly Ninject

Error: Could not load file or assembly ‘Ninject, Version=3.2.0.0, Culture=neutral, PublicKeyToken=c7192dc5380945e7’ or one of its dependencies. The system cannot find the file specified.

Above error started appearing suddenly in our local Sitecore (Sitecore.NET 8.1 (rev. 151207)) project. We eyed lot of articles on-line but none helped, So that is why I thought it’s better to blog this out. We investigated for couple of hours to get this fixed, may be this post saves someone’s time.

Before applying below given solution:
1) Check the version of Ninject in solution. If you have multiple projects in solution then check version in each project.
2) Check version in Web.config

If there is any change in versions then correct it by adding the proper assembly version in reference.

3) Try to reset IIS

Solution: In our case it was because of some problem with Application Pool. We tried to create a New Site in IIS along with new Application Pool. This fixed the problem. If you are also getting the same then you may try this.

If you know/guess the root cause of this then please add in comment. Thanks!